This invention relates to a seal. In more detail the invention relates to a reusable, tamper-indicating seal. In still more detail the invention relates to a seal constituting a fastener that serves as a check against tampering or unauthorized opening by clearly indicating within the seal if it has been opened.
Seals are employed on railway cars and other repositories of valuable materials as a safeguard against tampering or unauthorized opening. Conventional seals provide considerable assurance that unauthorized opening has not occurred. However such seals can be circumvented by anyone having access to a supply of seals by simply replacing a broken seal with a new one or counterfeiting seals would not be difficult for someone willing to go to considerable expense.
In some locations seals having a very high degree of required to indicate if unauthorized access has occurred. Seals presently employed for this purpose do have a high degree of integrity but at a relatively high cost both in time and money. To assure that a seal has not been replaced a plurality of random scratches are made on the interior of the seal and a picture thereof taken for recordation. When the seal is broken the pattern of scratches in the seal is compared with that in the records and an identical pattern indicates that the seal has not been replaced. This requirement for comparison is both expensive and time consuming. In addition the seal is destroyed when opened and since it cannot be reused a new seal must be installed.